I have used the Motorola Iridium phones in the past, but I understand there are more options out there. I do travel to locations other than Africa, such as the Galapagos and remote locations in the American West. I do understand that you can now purchase satellite phones with GPS already integrated into the handset. Thuraya comes to mind.
If you have any information on satellite phones, feel free to comment on this thread. Hmmm. I wonder if I should get system where I can update my blog from the middle of the Serengeti? A wifi hotspot in camp?